1. Field of the Invention
The invention relates to a device for opening a toilet flushing system.
2. Description of the Related Art
The invention relates more particularly to a toilet flushing device, of the type that comprises a water cistern fed via a tap connected to a water delivery network, and which is capable of being opened to cause the cistern to be filled when the water level descends below a determined lower limit, and of the type that comprises a bottom discharge orifice and a vertical mobile discharge valve element associated with this orifice which is capable of occupying a low closed position to keep the water inside the cistern or a high open position to discharge the water to a toilet pan, and of the type that comprises a float which, when the cistern is full, is submerged so as to push the valve element towards its open position, and of the type that comprises a means of locking the valve element that is capable of occupying a locked position to keep the valve element closed or of occupying an unlocked position to allow the float to pull the valve element from its closed position to its open position.
Several toilet flushing devices are known in which a device, which uses Archimedes' principle of buoyancy, makes it possible to transmit a pressure of a submerged float to a valve element for opening the cistern by means of a transmission mechanism such as a lever.
In such devices, the float is usually immobilized by means of a latching mechanism and when it is released it is capable of transmitting its upward movement to the valve element by means of the transmission mechanism to cause the said valve element to open.
Control of the latching mechanism may easily be provided by a solenoid or electromagnet operating at low voltage and in autonomous manner.
This configuration makes it possible in particular to propose automatically controlled flushing systems which, when the user leaves the toilet, automatically trigger the actuation of the element for opening the cistern in order to cause the water to be discharged to the toilet pan, the electromagnet then being controlled electronically.
This configuration, however effective it may be, nonetheless has some disadvantages.
To be able effectively to raise the valve element, the float must necessarily be arranged at the end of the lever. As a result, due to the bending deformations of the said lever, its position is not strictly defined in the cistern, so that it is necessary to provide a latching mechanism of large dimensions capable of interacting with the float even if the latter moves by a few millimeters.
Secondly, the transmission mechanism in itself is costly to produce.
Furthermore, the latching mechanism is also costly to produce, since it requires in effect at least one system comprising a cam interposed between the electromagnet and the float.
Finally, the float and transmission mechanism assembly occupies a considerable volume in the cistern, which makes the flushing system maintenance operations difficult, whether they be repair, cleaning or descaling operations.
To remedy this disadvantage, document WO-A-00/49237 has proposed a device arranged substantially coaxially with the discharge valve element, in order to reduce the number of elements used.
More particularly, document WO-A-00/49237 proposes a toilet flushing system opening device of the type previously described, in which the float is secured to the valve element and in which the locking means comprises a vertically mobile locking finger, substantially coaxial with the valve element and secured to the latter, the end of which is capable of being held laterally in a locked position or released in an unlocked position by the end of a tilting lever which is articulated relative to the cistern and which is capable of being actuated by a solenoid in order selectively to prevent or allow the finger and the valve element to rise under the action of the float in order to discharge the water into the toilet pan.
This design has numerous disadvantages.
On the one hand, the finger is secured to the valve element, which makes the mounting or removal of the assembly consisting of the finger and the valve element particularly tricky due to its bulk.
On the other hand, the complex design of the tilting lever is incompatible with an environment subject to high humidity. Specifically, limescale concretions, caused by the water contained in the cistern, may form on the articulation of the lever, or between the lever and the finger, and disrupt the smooth operation of the device.